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I would like to know how to improve the code on the css file because I don't really like how I just used selectors for every button in the respective section and I wonder how could I have done it better (like could I set them in one go without the need to repeat the same code with different values?). Thank you in advance!

I still find myself struggling to grasp the concepts of Flexbox and Grid, should you have any resources that helped you better understand this concepts I would ask you to share them with me. Thank you.